Mapei offers Dynamon SX626 and Dynamon SX550, hyperplasticising admixtures based on new generation of polycarboxlate ether. Dynamon SX626 / SX550 is a used waterproof and durable concrete with exposure class in compliance with EN206 -1, ready mixed concrete with high mechanical performance and good acceleration in the development of mechanical strength, making the concrete pumpable.
Precast building is constructed by assembling and connecting various prefabricated elements required in the building structure. These include :
- Precast SlabsPrecast Beams
- Precast Columns
- Precast Walls
- Precast foundations
Anchoring with expansive mortars and fixing with rapid setting binders: Excessive spanning of areas by precast concrete foundation sections with no fill and no footing at all may lead to future water entry, floor slab settlement, or in severe cases, foundation movement. Spans over five feet would violate a Superior Walls guideline, and other spans may be improper depending on the product and the engineering design for the project.
Repair precast concrete with mortars and controlled shrinkage binders: Concrete is typically “restrained” so changes in volume result in cracks because concrete is weak in tensile. Volume changes occur due to chemical and autogeneous shrinkage – both result in hydration.
Planitop: R2-class, rapid-setting shrinkage-compensated, thixotropic, fibre-reinforced, cementitious mortar applied in a single layer from 3 to 40 mm thick, for repairing and smoothing concrete. Planitop is used for:
- Quick repairs to deteriorated parts in concrete, the corners of beams, pillars, buffer walls, cornices, and the front edges of balconies.
- Quickly smoothing over surface defects in cast concrete, such as honeycombs, spacer holes, construction joints, etc, before painting the surface.
- Repairing and smoothing over concrete mouldings on civil buildings, such as skirt roofs and protruding decorative elements.
- Repairing precast concrete structures.
Eporip: Monolithic construction joints between fresh and hardened concrete. Bonding precast concrete element and bonding steel to concrete. Filling cracks in concrete. Eporip is a solvent-free epoxy adhesive consisting of two pre-measured components (component A = resin, component B = hardener) that have to be mixed before use. Eporip has the consistency of a slightly thixotropic paste that can be applied by brush on both horizontal and vertical surfaces.
Special basement waterproofing system details are needed if a basement de-watering system is installed after construction of a building with precast concrete foundations or walls.
Mapegum WPS: Quick-drying flexible liquid membrane for waterproofing internal surfaces. Waterproofing indoor floor and wall surfaces that are not subject to rising damp nor in permanent water immersion. Flexible, anti-fracture membrane. Apply before the installation of ceramic tiles or stone material. Mapegum WPS may be used on:
- plasterboard, gypsum or cementitious render, lightweight cement block and marine-plywood
- cementitious, anhydrite, wooden and magnesite substrates and existing ceramic and natural stone after the application of Eco Prim T primer.
Mapelastic Aquadefense: Ready-to-use, ultraquick drying, flexible liquid membrane for internal and external waterproofing applications. It is used to form waterproofing layers before applying ceramic, stone and mosaic coatings in: balconies and terraces; bathrooms and shower cubicles; laundry rooms; saunas and damp environments in general.
Mapeflex PU45: Specially developed for sealing expansion and distribution joints in horizontal and vertical surfaces, including those which are subject to occasional chemical attack provoked by hydrocarbons. It is also recommended for flexible bonds between similar and different materials most commonly used in the building industry for both internal and external applications and as a replacement or to integrate mechanical fasteners.
Protection of Precast Concrete
Degradation of concrete includes the following common mechanisms: Acidic reactions, alkaline reactions, chloride-induced deterioration, and sulfate deterioration. Each is produced by different environmental conditions. Concrete is also highly alkaline and contains moisture, which can prevent a coating from adhering to the surface, curing properly, or performing as needed.
Tunnel formwork type of residential project in Pune
The project consultant was awarded with the design and implementation of precast segments and cast-in-situ concrete of M60 grade in the BOQ. With many trials, Mapei India came up with the required admixture for the project and Dynamon SX626 was used for the GCC + 13 Floors structure.